Fluids are located underground. The fluids can include hydrocarbons (oil) and water, for example. Extraction of at least the oil for consumption is desirable. A hole is drilled into the ground to extract the fluids. The hole is called a wellbore and is oftentimes cased with a metal tubular structure referred to as a casing. A number of other features such as cementing between the casing and the wellbore can be added. The wellbore can be essentially vertical, and can even be drilled in various directions, e.g. upward or horizontal.
Once the wellbore is cased, the casing can be perforated. Perforating involves creating holes in the casing thereby connecting the wellbore outside of the casing to the inside of the casing. That can be done by lowering a perforating gun into the casing. The perforating gun has charges that detonate and propel matter through the casing thereby creating the holes in the casing and the surrounding formation to help formation fluids flow from the formation and wellbore into the casing.
Sometimes the formation has enough pressure to drive well fluids uphole to surface. However, that situation is not always present and cannot be relied upon. Artificial lift devices can therefore be used to drive downhole well fluids uphole, e.g., to surface. The artificial lift devices are placed downhole inside the casing. An artificial lift device often has an electric motor with internal parts. Preventing well fluids from reaching component parts of the motor is desirable.